If you have a teacher or you are next to a piano, it will be easier to determine your vocal range. You can also sing independently in the solfeggio pattern. You can begin from the lowest range and move to the highest range, paying attention to what is the most comfortable. Do not press the voice, as you may further damage your vocal chords. When you have defined the most comfortable range, start singing lower until you cannot sing in tune with the piano. Go back one half-step higher. This is your lowest note from the vocal range. Then, start singing higher until you cannot sing in tune with the piano. Go back one-step lower. This is your highest note from the vocal range. Measure the number of octaves between the notes. Each octave is 12 notes. Therefore, divide the full number of semitones in the ranger by 12. You will get the number of octaves.